* master:
  Fix version
  Improve the consistency of commit titles, branch names, tag names, issue/MR titles, on their respective project pages
  Update CHANGELOG [ci skip]
  Add some cosmetic changes to variables API documentation [ci skip]
  Modify builds API documentation style [ci skip]
  Modify :ci_variable factory
  Add 'Build' prefix to Variables entry name in API docs index
  Fix some typos
  Add some fixes after review
  Remove blank line
  Update ./doc/api
  Change :variable_id to :key as resource ID in API
  Fix a typo in method description
  Add create feature to variables API
  Add missing 'not_found' checks in variables API
  Add delete feature to variables API
  Add update feature for variables API
  Add features for list and show details of variables in API

Conflicts:
	doc/api/README.md
	lib/api/entities.rb